The theory behind the use of apple cider vinegar is that because the mammalian body's blood pH is slightly alkaline, with a normal range of 7.36-7.44, our diet and drinking water should reflect this preference. While apple cider vinegar is actually acidic when consumed, when it is digested in the body it becomes alkalizing. This acid-to-alkaline process also occurs when the body metabolizes most vegetables.

The theory is that an imbalanced, acidic diet high in animal protein, sugar, caffeine and processed foods tends to disrupt this pH balance. This robs the body of alkaline minerals such as sodium, potassium, magnesium and calcium and leaves us prone to chronic and degenerative diseases. A 2016 meta-analysis of published studies titled "The Alkaline Diet: Is There Evidence That an Alkaline pH Diet Benefits Health?", found that increased fruits and vegetables in an alkaline diet would improve the K/Na ratio and may benefit bone health, reduce muscle wasting, as well as mitigate other chronic diseases such as hypertension and strokes.